That's a pretty small list, considering there are almost 200 countries in the world, and the U.S. isn't on great terms with all of them.
But what really matters is if the State Department says the countries have "repeatedly provided support for acts of international terrorism." If they're on the list, they're subject to economic sanctions and trading restrictions.
Cuba was first put on the list in 1982, for supporting leftist guerrilla movements in Latin America and Africa, according to the U.S. The State Department says Cuba hasn't sponsored international terrorism in the past six months, which is the deciding factor for being taken off the list.
In some ways it's surprising that those are the only countries on the list. More have been on it before, but were since taken off.
Iraq, Libya and North Korea were also on the list before. So was South Yemen, which was taken off the list when it later merged with North Yemen.
Yemen, Iraq, Libya and North Korea don't exactly sound like countries the U.S. sees as particularly friendly. But what matters is whether or not they're sponsoring international terrorism, and they can always be put back on the list.
The State Department had Iraq on the list from 1979-1982. After a brief reprieve it was put back on from 1990-2004. It was taken off after the fall of Saddam Hussein.
And North Korea has actually been considered for being put back on the list. The Wall Street Journal reported the Obama administration considered putting the country back on the list after the Sony hack last year.
So this doesn't mean Cuba is necessarily in the clear.
But for now it will see the benefits of the lifting of those sanctions. And this is an important step toward normal diplomatic relations between the U.S. and Cuba.
This video includes music by Brenticus / CC BY 3.0.